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1

Übungsaufgaben 5./6. Semester / Flugmechanik Übung 4

« on: February 24, 2011, 07:32:14 pm »

You get two different values for VHL, lying exactly on the limit lines. There is no for them to be equal, the -10% and 45% are just random definitions I think. Now you will have to check which one is  greater. This is the minimum value of VHL you need to have in order to  control the aircraft.

Thanks Zwepac. That makes sense. Just a small question. Did you Ca as Camax = 1.25? Or the Ca for the minimum radius in Aufgabe 2, Ca = 1.24?

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Übungsaufgaben 5./6. Semester / Flugmechanik Übung 4

« on: February 24, 2011, 06:52:47 pm »

hey guys

I have a doubt in Uebung 6 Aufgabe 4.

What value of Ca did you use? The Ca.max = 1.25?

I'm doing the calculation for the front and rear limits, based on the slide 4.2-5.

The only thing I change from one to the other are the values of:

Xs25 / lu = 0.45 => Cah.max = 1
Xs25 / lu = -0.1 => Cah.min = -1.3

And with these two combinations I get two different values for Sh. So, how is it possible to get a unified value that satisfies both cases? Something wrong with the Ca maybe? Can someone explain me?

I also assume lu = Sf / bf = 1.393 m, since the wing is rectangular.

I'm sorry for the English, I'm an Erasmus student and it's still too complicated to try and write in German without spending too much time. I hope you can understand